The present invention relates to an attribute information presenting apparatus for presenting attribute information such as sound information and picture information to be indicated to a reference point by an object according to the relative position of the object to the reference point.
The technology for realizing the function of stereo enhancement effect for enhancing the spreading sensation of stereo sound only by two speakers connected to a personal computer has been developed. This stereo enhancement effect is an acoustic effect of amplifying the spreading sensation of stereo sound in the horizontal direction, and by varying the frequency characteristic and phase of sound signal, the sound is heard from outside of the installed positions of the right and left speakers, and the depth sensation of sound is also increased.
This stereo enhancement effect is one of the acoustic effects created by the function known as three-dimensional sound. The three-dimensional sound is a function for realizing a solid acoustic effect by using two speakers, and by using only two speakers installed at specified positions, the sound is heard from the vertical, lateral and front-rear directions of the listener, that is, from all directions of the three-dimensional space surrounding the listener.
The three-dimensional sound possesses, in addition to the above acoustic effect of stereo enhancement effect, an acoustic effect of reproducing reflected sound and reverberation of a concert hall (sound field control), and an acoustic effect of moving a specific sound source freely so that the sound should be heard from an arbitrary direction of the listener (sound image localization). These acoustic effects are realized by varying the frequency characteristics and phase of the sound signal from two speakers in consideration of changes of frequency characteristic from the sound source until the sound actually reaches the ears of the listener.
Therefore, if the relative positions of the sound generating and moving object and the listener (viewer point) are different, sound signals having frequency characteristic and phase suited to the relative positions must be emitted from two speakers. In this case, hitherto, relative coordinates of the object to the viewer point are inputted, and audio data corresponding to the relative coordinates are created from the model audio data by using a filter circuit and others.
Besides, the technology for creating picture information such as object shape, color and texture, aside from the sound information, according to the relative position of the object to the viewer point has been also developed. In this case, same as in the case of sound, image data depending on the relative coordinates is created from the model image data.
FIG. 1 is a diagram showing the principle of a conventional attribute information presenting apparatus. The prior art has a relative coordinate input unit 101 for entering relative coordinates (r, .theta., .phi.) of the object to the viewpoint expressed in polar coordinates, a model storage unit 102 for storing the model of various attribute information including object shape, color, texture, and sound, and a data creating unit 103 for creating data of desired attribute information on the basis of each model in the model storage unit 102 according to the relative coordinates inputted from the relative coordinate input unit 101. When relative coordinates of the object to the viewer point are inputted in the data creating unit 103 through the relative coordinate input unit 101, the model data of the object is read out from the model storage unit 102. In the data creating unit 103, the data of the attribute information at the point when the model data reaches the viewer point is created and delivered on the basis of the model data.
In this prior art, the processing quantity in the data creating unit 103 is huge when creating data of attribute information according to the relative coordinates inputted from the relative coordinate input unit 101. Therefore, for creating and processing in real time, a high speed system is indispensable, which results in a high cost. Or, if the object moves very fast, even by using a high speed system, the creating and processing speed cannot follow up the changes of relative coordinates, and data of attribute information cannot be created in real time.
Also in the prior art, while the object and/or viewer point is moving, it is necessary to re-calculate the relative coordinates of the object to the viewpoint point all the time and input from the relative coordinate input unit 101, and it demands tremendous labor in input of relative coordinates.